Alex- Part 2 Flashcards
Lobotomies
Antonia moniz, ice pick method, trans orbital, severed tissue from pfc. 60% women patients, way to manage behaviour. Affects judgement, planning, awareness but can lead to losing complete autonomy. Helped clear out mental asylums and prisons. Replaced by drugs like neuroleptics for schizo, reversable
Executive control
Norman and shallice 80: needed for planning , problems, new situations, overcoming habitual response, danger. Homunculus problem, who makes decisions e.g. a person but then who makes that so person within person. Need to coordinate time management, motivation, inhibition, monitoring
Pfc background
Split into orbitofrontal pfc/ventral and dlpfc. Has attention, memory, emotion bianchi 1800 found these disrupted in dogs and monkey when severed. Brodmann: 29% cortex in humans, 19% chimps, less in cats. Enlarged pfc distinct to humans and primates , uses lots of metabolic energy , highly connected across brain
Key parts
Dlpfc play a role in memory, attention, goal setting anf motivation, inhibition
Latera; fpc has subjective self, humour, tom
Vpfc has social and emotional functins, self regulation
Dlpc
Has inhibition and initiation. Inhibition split into restraining potential behaviour, preventing info from interfering W processing, stopping inappropriate actions, removing irrelevant info from wm.
Tasks to measure dlpfc
Oddball task schrueder: initiate behaviour when see odd one out, measures event related potential. Go/no go cornet, measures inhibition. Strop task, low level features interfere w high, links between dlpc memory and anterior cingulate/attention. Schizophrenic worse at both
Ventromedial pfc
Links between stim and actions, needed for adaptive learning from reward and punishment, social decision making, emotional regulation. Connection W amygdala. Benoit 2014, create mental model of familiar and not places, familiar linked to vpfc. Brain damage leads to acquired sociopathy, poor impulse but feel bad,
Phineas gage
Before: hard worker, responsible, good humoured. After: lazy, unreliable, irresponsible, vulgar, inappropriate, lost sense of humour
Frontal cortex damaged so loss of inhibition
Cognitive flexibility
Adjust thinking from old situations to new, overcome habitual repose, switch between diff rules. Cog shifting is conscious but task unconscious. A not b task, Wisconsin sorting task, sort to diff rules, damage still use old rules. Eriksen flanker task: inhibit prepotent response, measures attention in anterior cingulate. Guildford’s alternative uses task - creativity
Disrupted inhibition
Medial pfc needed for goal directed, stroke in lateral but not ventromedial show aboulia (lethargy, quiet, distracted). Ps W pfc damage imitate bahbiour, alien hand syndrome, utilisation behaviour (engage in using objects if placed instant) as can’t inhibit
Diffs in damage
To dlpfc has impaired set shifting, response inhibition, motivation
Vmpfc has impulsive behvaiour, utlilization, imitation
Tutorial
Substantia nigra has less melanin in parkinsons, less to protect from cell death.hemiballismus is one side has dance like moves, damage to sub thalamus nucleus. Loss of dopamine also means issues in rated network and other cog issues. DBS: on the subthalamic nucleus, globus pallidus, risk of infection, cog decline. Dopamine meds lead to psychoticism and motor issues. Lewy body has memory and motor issues
Defining decision
Libet: arises endogenously- not a response to a cue, no external restrictions/own free will, subjects feel they are performing act on their own. Broader definition: at least 2 choices, execrations can be predicted about outcomes, value of outcome can be assessed
Normative theories of decision - utility
Id of optimal decision making, normative is the ideal, based on probability and expected value e.g. cost benefit analysis. Utility is what something is worth to you, not always directly linked to value. Rationality theory: want to max expected utility, increase in value decreases risk. Effected by psych as framing effect: neg info highlighted, less likely to pick even if same. W: Donets reflect real behaviour e.g. lottery
Prospect theory - tversky
Predicts what people will not should do. Reference dependence: ppl make decisions based on anticipated gains and losses compared to current state. Probability weighting: probs subjectively assessed e.g. overestimate ability to win lottery. Can map loss aversion- risk averse for high prob gains, risk seeking for low, more sensitive to losses
Heuristics in decision making
May account for lack of rationality- bounded rationality allows ppl to solve problems within limitations- expressed as mental shortcuts/bias
Availability heuristic
bias toward more immediate examples that come to mind- more easily recalled, more relevant to you e.g. tversky, e.g. jaws- people killing sharks as they think they are violent
Representative heuristic
degree to which an event is similar to its parent population and reflects the salient features- focus on a stereotype of a given category. Could lead to racism but could use past experiences climbing to help others in danger
Anchoring and adjustment
anchoring is when we make assessments by starting from an implicit or explicit initial anchor, adjustment is failure to move away from this. Hard to avoid- strack97: ppl told gandhi dies v old or v young, estimates were younger in young and older in old. Affected by precision of the anchor - more spec, anchor more closely
Nash equilibrium
Each p has strategy, no player has incentive to change given what other is doing e.g. both cooperate get 6 pounds, one does one doesn’t one gets 10, other 1, if both don’t both get 3- NE is that they both shouldn’t as neither player can get advantage by doing something else/whatever does, you still benefit
Neural mechanisms
Primary reinforcers are direct benefits like food and water, secondary are when rewards can be used to gain other rewards, no value itself e.g. like money
Aversive are removal of reinforcers, aversive stim like guilt, pain, loss. Dopamine linked to reward prediction. In addiction are over stim so increased tolerance
Online games
Designed to be addictive as secondary reinforcement like lights, sounds, graphics, punishments like cost. Instant to delayed gratification as the game goes on. Pay for loss aversion. Endowed progress bias: reward like progressing through map, linked to sunk cost bias as don’t want to quit if progress. Envy, online friendships. Spending correlates to problem gambling young people
